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Post by pinkie on Jun 29, 2015 7:08:15 GMT
With apologies to Monty Python - but this is my roots. There is nothing wrong with evolving, striving to perfect, and varying existing technology. But Pink Triangle was about thinking out of the box and pushing the boundaries. The Pip amplifier launched under that brand pioneered the transconductance idea (among others). And this latest product from the same designer, pioneers truly new design ideas (many of them patented to THX, Jones, and Fincham, or combinations of them). To quote the last paragraph of the user manual "In summary, Benchmark has taken a radical approach to audio amplification, has leveraged patented technologies (licenced from THX Ltd) and has reversed many common practices. The result is an amplifier that is significantly quieter, cleaner, smaller, and more efficient than any traditional design. There is nothing ordinary about the Benchmark AHB2" Designed for the pro-market where it was launched to huge acclaim, it is rapidly getting recognition in the audiophile market. Now that I have one nestled in my system, its not hard to see why. EXTRAordinary.  |
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Post by pinkie on Jun 29, 2015 7:21:35 GMT
A bit more from John Siau of Benchmark, before I start chipping in my two penn'th
"The AHB2 will sound different than other amplifiers...The THX patents gave us a tool to virtually eliminate distortion from high-power push-pull output stages. In developing the product, we focused on distortion, frequency response, phase accuracy, damping factor, noise, and efficiency ... in that order
...
The AHB2 is not intended to enhance or sweeten the music. Its job is to render a near perfect high-power replica of the incoming line-level signal. It does this very well. Consequently it may sound significantly different than other amplifiers. Familiar amplifier-induced distortion components are gone, and this will often be perceived as a change in frequency response. Low-frequency distortion can give the impression of increased bass, but this distortion is absent in the AHB2. Likewise, the AHB2 does not have the familiar high-frequency push-pull crossover distortion, or the high-frequency sizzle produced by class D amplifiers. This absence of distortion may give the impression of a reduced high-frequency response. But, after adapting to this difference, the result is a natural and non-fatiguing listening experience. At the end of a long day transparency wins.
The performance of the AHB2 is dramatically different than that of other power amplifiers. It is at least 15 dB quieter than all other amplifiers, and is 30 dB quieter than most. "
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Post by pinkie on Jun 29, 2015 8:08:13 GMT
I could take it out and take better pictures, but they wouldn't be as good as any of the countless photos you can find with a 5 second google search This gives a sense of scale most will recognise  |
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Post by pinkie on Jun 29, 2015 8:28:41 GMT
The Benchmark manual refers to it achieving "vanishingly low levels of distortion". To put that in perspective, by comparison with the amp I have been drooling over on this forum - Martin T's Chord 1200, in its latest MkII spec
Chord signal to noise ratio -97db (I assume A-weighted) distortion 0.06%
Benchmark signal to noise ratio -132db (A weighted) -130db unweighted 20Hz to 20KHz. Distortion (forget the directly comparable, how about 1KHz, 20KHz at full rated power into any rated load - 0.00011% stereo mode (0.00010% mono mode)
I realise measurements aren't everything, and this is a forum where there are many subjectivists. But good measurements don't need to mean bad sound! It listens as good as it measures. If some subjectivists talk about "windows onto the music" and "clearing away levels of grime", then noise and distortion are grime on the window. You may not be able to see them if your eyes have dimmed, or the other optical equipment you are looking through (like your glasses) have their own dirt on them, but that doesn't mean that grime on the amplifier window (noise, distortion) don't affect your ability to see the music through the window. Maybe you like a bit of fog, like a pastel filter on a camera creates a warmer softer picture, a "Renoir" effect, but if you are after clean windows you don't want distortion or noise.
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Post by MartinT on Jun 29, 2015 8:47:02 GMT
Interesting that you report on exceptional sound quality, Richard. The Benchmark features a switched-mode power supply, just like my Chord. It gives the lie to claims that a switched-mode power supply "has no place in a hi-fi system", as I've read several times by those who don't know. Anyone who does know, will understand that a well-designed and shielded SMPS in a power amp will respond to sudden current demand far better than a standard regulated supply, and can keep matched and balanced the +ve and -ve rails, in a much more compact unit and generating much less heat. Now then, I might have allowed the SQ claims to pass me by but since Bascom H. King has reviewed it so well, my interest is piqued, rather like anything created by Nelson Pass. I'd like to try one in my system. |
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Post by pinkie on Jun 29, 2015 9:11:20 GMT
Interesting that you report on exceptional sound quality, Richard. The Benchmark features a switched-mode power supply, just like my Chord. It gives the lie to claims that a switched-mode power supply "has no place in a hi-fi system", as I've read several times by those who don't know. Anyone who does know, will understand that a well-designed and shielded SMPS in a power amp will respond to sudden current demand far better than a standard regulated supply, and can keep matched and balanced the +ve and -ve rails, in a much more compact unit and generating much less heat. Now then, I might have allowed the SQ claims to pass me by but since Bascom H. King has reviewed it so well, my interest is piqued, rather like anything created by Nelson Pass. I'd like to try one in my system. Well, I'd like to hear the Chord. I need to catch up work. The nightmare of French bureacracy - buying a house, and with a mortgage, and additional land from a 2nd vendor - is a huge "distraction", and changing cars took my eye off the ball a bit. If I catch up, maybe we could get together Regarding the power supply - it is actually a resonant switch-mode power supply. In addition to the benefits you mention, and the lack of large stray magnetic fields from transformers, resonant supplies switch at low voltage and low current and are much quieter than traditional switching supplies |
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Post by pinkie on Jun 29, 2015 9:20:38 GMT
I'm taking my time with the sound quality. I have probably only managed a handful of hours listening to date. With the arrival of the benchmark I changed preamp (the Pip 2 returned), interconnects (Pip 2 is RCA, Pip 1 Din, and the Benchmark only accepts balanced inputs) and I took the opportunity to adjust the antiskate with HFS69 and a 'scope. The speakers have also had their outer skin re-taughtened. So everything is a bit new. I want to do more listening once I have acclimatised - and later to switch in the Ventricals to try a different load and sound on both amps. First impressions are Very fast. Real control. Nothing dramatic or "in your face" just very distinct tight music More extended bass (yes I know what John Siau said about reduced distortion seeming like less bass, but I think its just got more outright grunt down there than the Quad has) Very relaxed - almost to the point of dull - but in the way the ESL's themselves sound dull - ie Not false bright. Subtle detail. Half the records I've played have sneaked out when I wasn't looking and added some BV's. Those vocals now have more distinct voices rather than a "choir" effect Much more enjoyable at low listening levels. I couldn't wait for a decent neighbour friendly time to listen this morning, and was surprised how "life like" they were at much lower levels than I would normally listen. With the Quad (I should really say "the previous setup") - low level listening was always a bit flat and "not proper" But early days. The good news is Sue refers to the Benchmark as that "nice small black one" and the Quad as the "big ugly grey one". Promising!  |
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Post by MartinT on Jun 29, 2015 9:23:37 GMT
All very interesting, but the Quad is not a reference that has any meaning for me, being distinctly average.
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Post by pinkie on Jun 29, 2015 9:32:37 GMT
All very interesting, but the Quad is not a reference that has any meaning for me, being distinctly average. Ah yes I can see that. It only needs fairly small changes to dramatically improve the Quad though, and my modified version has acquitted itself well against most "reasonable price" amplifiers (it was a damn site better than the Arcam I suffered as a temp replacement for a while). Just un-knitting the mains wiring from the signal wiring works wonders. Not sure what the opamps do - because all mods were done at once, but better opamps is a standard mod. Dropping the input sensitivity helps the noise performance, and sorting out the bridge really moves it up a level. In a way - the Benchmark is another take on current dumping - in that it lets chunky class AB devices deliver the power, and uses "correction circuitry" to get the output right. Edit: And if you look at a handful of the reviews it is not like it is only "better than a 405-2) For example HiFi News and Record Review |
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Post by pinkie on Jun 29, 2015 9:48:08 GMT
Now then, I might have allowed the SQ claims to pass me by but since Bascom H. King has reviewed it so well, my interest is piqued, rather like anything created by Nelson Pass. I'd like to try one in my system. I'd not seen that review before (I thought I had read most). The basic conclusion is the same as every review I've read - I haven't found a dissenting one yet. Everything Audio Network Stellar Sound Award. Yup - I'd go along with that |
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Post by dvh on Jun 29, 2015 12:56:44 GMT
Designed for the pro-market where it was launched to huge acclaim, it is rapidly getting recognition in the audiophile market. Now that I have one nestled in my system, its not hard to see why. EXTRAordinary. Just for clarification; have you bought this amp, or have you just borrowed it? |
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Post by pinkie on Jun 29, 2015 13:11:06 GMT
I have it on loan. I think I am likely (almost certain) to buy one - but it may have to wait until after we finish the move to France. What difference does it make to whether it is either interesting because of its design innovations or interesting because of how it sounds?
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Post by dvh on Jun 29, 2015 13:18:18 GMT
I have it on loan. I think I am likely (almost certain) to buy one - but it may have to wait until after we finish the move to France. What difference does it make to whether it is either interesting because of its design innovations or interesting because of how it sounds? Thanks for the clarification. There's a huge difference IMO between 'this amp is innovative and sounds good' and 'I like this amp's sound so much I bought one'. |
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Post by ChrisB on Jun 29, 2015 13:28:21 GMT
Richard, whether you intend to buy this amp or not, I think it would be proper for you to clearly make a declaration of your interests with the designer, maker or whoever it might be, and to do it here in this thread. This way, anyone reading it will be able to decide for themselves whether they think that has influenced what you have written.
You often walk a fine line with your posts here about your friends and ex-colleagues work and I think you should be crystal clear about this, as apart from our regulars, we have other people visiting TAS who may not necessarily have read any of your other posts.
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Post by MartinT on Jun 29, 2015 13:38:18 GMT
Indeed, Richard, we would like to know that the 'same designer' you mention in the O/P is not associated with your business(es) now. If you do buy one, please let us know as it does add credibility to any review. Thanks.
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Post by pinkie on Jun 29, 2015 13:56:47 GMT
The amplifier is sold by Benchmark - a large American corporation I have nothing to do with. It's design was purchased from THX (owned by George Lucas) and managed by Lawrie Fincham (formerly of Kef). It uses patented new technologies developed by Lawrie Fincham and Owen Jones for THX (and themselves I think - tbh, apart from seeing Owen and Lawries name on one of the patents when I googled I have no idea about the patent arrangements. Owen Jones, a personal friend of mine, who I first met when he was at Pink Triangle more than 25 years ago, and who designed the Pip did the vast majority of the design and testing work for the amplifier - and I have been watching the project develop over the last couple of years when I visit him. Benchmark product launch - stereophileNeither Owen nor I have any direct financial interest in THX (owned by George Lucas) or Benchmark (John Siau) nor this amplifier. He's just a bit chuffed so many people like it. And I find it interesting in a world that so often is a bit dull and "me too" that proper engineering and talent and innovation can produce something exceptional. Just google to see what the rest of the world thinks about it Would you prefer to remain in the dark ? That's not a problem |
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Post by pinkie on Jun 29, 2015 14:05:25 GMT
I have it on loan. I think I am likely (almost certain) to buy one - but it may have to wait until after we finish the move to France. What difference does it make to whether it is either interesting because of its design innovations or interesting because of how it sounds? Thanks for the clarification. There's a huge difference IMO between 'this amp is innovative and sounds good' and 'I like this amp's sound so much I bought one'. That's fair enough. As I noted above - it's early days, and I made a lot of changes this weekend. £3000 is more than I routinely spend as pocket money. So I won't be rushing into any decisions. I also need to conserve cash until we have moved to France because the purchase on a mortgage is a bit tight for funds, until we are able to sell up in the UK and release some equity. I cannot conceive of spending £3000 on an amplifier without listening to it extensively. I have just had the opportunity to do that, and I am relishing it. But I have only just started the process. I have had another couple of quick listens, and I think it inconceivable I won't buy one as soon as I am able to. Once you stop "listening" - as an active "is it any good" exercise, and just play records - then its very subtle benefits become SOO obvious. It's one of those "I must play all my records on it to listen to them again" sort of products. Surely a forum is to talk about things that are interesting. Do I have to buy something to talk about it? |
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Post by dvh on Jun 29, 2015 14:16:15 GMT
Thanks for the clarification. There's a huge difference IMO between 'this amp is innovative and sounds good' and 'I like this amp's sound so much I bought one'. That's fair enough. As I noted above - it's early days, and I made a lot of changes this weekend. £3000 is more than I routinely spend as pocket money. So I won't be rushing into any decisions. I also need to conserve cash until we have moved to France because the purchase on a mortgage is a bit tight for funds, until we are able to sell up in the UK and release some equity. I cannot conceive of spending £3000 on an amplifier without listening to it extensively. I have just had the opportunity to do that, and I am relishing it. But I have only just started the process. I have had another couple of quick listens, and I think it inconceivable I won't buy one as soon as I am able to. Once you stop "listening" - as an active "is it any good" exercise, and just play records - then its very subtle benefits become SOO obvious. It's one of those "I must play all my records on it to listen to them again" sort of products. Surely a forum is to talk about things that are interesting. Do I have to buy something to talk about it? Of course not. I was guilty of speed-reading your posts, and took the phrase 'I have one nestling in my system' to mean you had actually bought one. As you say, £3k is a lot to spend 'on spec'. |
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Post by MartinT on Jun 29, 2015 14:30:06 GMT
Would you prefer to remain in the dark ? That's not a problem Not at all, it's just important to us that reviews and enthusiasm for a product are set in the correct context. Thanks for the information.
I see that Audio Affair are a dealer, I know them so shall make enquiries.
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Post by pinkie on Jun 29, 2015 14:50:42 GMT
OK Thanks Martin. I knew that really. I forget that within the world of forums some people seem more worried about the rules than just chatting about whats interesting. At least here that is free from blatant hostility and childish name-calling. But I struggle enough with the admin burden of working out which forum to post new threads in (its just TAS as far as I'm concerned) - without the pseudo-legal declarations of integrity. As I said before - it will be interesting to see what you think compared with the Chord. I am slightly wary about being interested to hear the Chord in case its much better. I had no intention of spending £3000 on an amplifier before this came along, but £8000 is divorce territory. I think I might prefer to die wondering  |
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